The center of our Galaxy hosts a Super-Massive Black Hole (SMBH). Since it has been argued that the SMBH can accelerate particles up to very high energies, its current and past activity must contribute to the population of Galactic cosmic-rays (CRs), the energetic particles that pervade the Galaxy. Understanding how CR are accelerated and how they propagate into the Central Molecular Zone (CMZ) is fundamental to understand if a strong outflow from the central regions powered by the intense star formation and supernova activity is enough to explain how the Fermi bubbles are powered, or if one has to rely on a past huge energy output from the SMBH.

Here we propose to investigate the morphology of the diffuse emission in the central 100 pc of the Galaxy in the high energy range of the FERMI-LAT and study the connection with the emission seen at very high energy with HESS. A dedicated re-analysis of the LAT data in the high energy band (up to 50-100 GeV) and the study of the morphological evolution of the diffuse emission over the whole central 200 pc as well as in the vicinity of the SMBH, will allow to characterize the evolution of the CR spatial distribution with energy. After removing all disk contributions, a search for lower surface brightness emission at highest latitude that could be associated with an outflow of CR from the GC and connected to the Fermi Bubles will be performed.